Guitar Amplifiers - How They Work

Guitar amplifiers are important equipment when it comes to playing electric guitars. This article contains information regarding guitar amplifiers, how they work, and which are the best amplifiers for beginners...

Guitar Amplifiers Explained

You will essentially need an amplifier if you want to play an electric or an acoustic guitar with a pickup. In simple words, a guitar amplifier is the equipment to which the guitar is connected via a cable, and may have a large speaker inside. The amplifier provides the function of amplifying guitar sound, and with the help of setting controls located on it, changing the way your guitar sounds. If you have inappropriate settings on the amplifier controls, your guitar's sound and the tone coming out of it will sound unprofessional. Hence, it is very necessary to learn how to use this necessary and important piece of equipment.

Earlier Stages

Guitar amplifiers have been around in the music scene for approximately 80 years now, and were first seen in the 1930s. In olden days, these sound boosters had basic features which did not give good treble and bass effect. Several different features and functionalities added up over time as amplifiers became more advanced. Throughout the 1960s, these equipment largely developed to where they are in today's world. Unlike today, earlier amps did not have distortion and other effect controls, so guitarists had to purposely boost volumes to limits for producing the distortion effect. However, today, there are many amplifiers which come along with an inbuilt distortion and several other guitar effects.

Types

There are fundamentally two kinds of guitar amplifiers, solid state and vacuum tube amplifiers. In addition to this, there are few which use a blend of both solid state and tube technologies. A majority of amplifiers, especially the less costly ones, are solid state, as they are lighter and easily repairable as compared to vacuum tube ones. However, most of the professional guitar players prefer to use tube ones because of the amplifiers' analog sensitivity, which they consider a reason for better sound. Tube amplifiers are more expensive, and can cost up to $500 to $1000, depending on the brand, sound quality, and features. Beginners usually cannot afford to spend such a huge amount on buying a tube guitar amplifier. That is why solid state amplifiers, which are more affordable, are recommended for novice guitar players.

Every kind of guitar amp has a specific watt power. More the wattage, louder would be the sound produced by the equipment. Those who want to use amps for small gigs should use at least 30-watt amplifiers, but those who want to use them at larger venues would require minimum 50-watt amplifiers. If you are thinking of the best guitar amplifiers for beginners, for home or studio purpose, you can choose a 10 or 20 watt amp of any well-known brand.

How They Work

The internal operation conventionally has four levels like input, signal modulation, signal amplification, and eventually the output level when the sound comes out. Let us discuss them in detail.

The Input LevelIn this working level, the amplifier takes in the input signal either from the pre-amplifier or straight from the guitar. If the guitar signal level is too low to be sent to the amplifier, the signal is first required to go through a pre-amplifier. It is crucial that there is an appropriate resistance corresponding with the input signal impedance and the amplifier's input signal impedance. Usually, signal resistance not matching is the cause of impairment of the guitar sound on the speaker unit.

At present, there are several different guitar amplifiers that have a pre-amplifier built in. In case of such amplification, there is no need to pass the guitar signal into a pre-amplifier individually. You can directly connect the cable to the amplifier itself.

The Signal Modulation LevelA plain guitar sound is not what a guitarist would generally prefer. He may need the sound output to be juiced up, twangy, funky, heavily distorted, etc. For getting such tones, the input signal is required to pass through a modulation before the sound is amplified. For instance, if the guitarist desires a heavy distortion or an overdrive tone, the guitar's plain sound passes through the needed distortion or any other required effect. This creates the many different guitar tones that we can hear in rock music. The same sequence applies to other guitar effects such as wah-wah, reverb, flanger, metal, etc. Most of today's guitar amplifiers consist of equalizers and other tone control knobs, all of which are under the signal modulation level. These equalizers and tone control knobs enable musicians to play with feedback loops and sound effects, which electronically alter the audio characteristics.

The Signal Amplification Stage and the OutputThe signal amplification stage is when the raw guitar sound is actually amplified. After this level comes the final output stage when the sound boost is thrown out of the speaker. In few inexpensive amplifiers, the outgoing signal after the amplification is straightaway passed into the speaker unit. Nevertheless, quality amplifiers have proper signal conditioning output stage where it is made sure that the output signal is suitably equalized to input specifications of the speaker unit.

Buying a Guitar Amplifier

The guitar playing capability and tones of a guitarist largely depend on the quality of amplifier and settings made on it. Every guitar player should essentially have a good understanding of amplifiers and pre-amplifiers, and their functions. If you want to buy an amplifier, learn about the advantages, disadvantages, and uses of both, solid state and vacuum tube amplifiers, and then go for the buy. It is also recommended to consult with a professional guitarist before buying. You may even take the help of salesmen in music instrument shops to help you decide which one would be most appropriate for your use.

Choosing a good amplifier is very significant if you want the guitar to sound its best. If you want the best ones, there are many brands to choose from; such as Marshall, Line 6, Peavey, Laney, and many other reputed brands. After reading the above article you should have some understanding about guitar amplifiers, how they work, and their importance.